xref: /llvm-project/libcxx/include/__algorithm/ranges_rotate.h (revision d10dc5a06fac4dcabf2264c64c8672c6f6ae36fb)
1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef _LIBCPP___ALGORITHM_RANGES_ROTATE_H
10 #define _LIBCPP___ALGORITHM_RANGES_ROTATE_H
11 
12 #include <__algorithm/iterator_operations.h>
13 #include <__algorithm/ranges_iterator_concept.h>
14 #include <__algorithm/rotate.h>
15 #include <__config>
16 #include <__iterator/concepts.h>
17 #include <__iterator/iterator_traits.h>
18 #include <__iterator/permutable.h>
19 #include <__ranges/access.h>
20 #include <__ranges/concepts.h>
21 #include <__ranges/subrange.h>
22 #include <__utility/move.h>
23 
24 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
25 #  pragma GCC system_header
26 #endif
27 
28 _LIBCPP_PUSH_MACROS
29 #include <__undef_macros>
30 
31 #if _LIBCPP_STD_VER >= 20
32 
33 _LIBCPP_BEGIN_NAMESPACE_STD
34 
35 namespace ranges {
36 struct __rotate {
37   template <class _Iter, class _Sent>
38   _LIBCPP_HIDE_FROM_ABI constexpr static subrange<_Iter> __rotate_fn_impl(_Iter __first, _Iter __middle, _Sent __last) {
39     auto __ret = std::__rotate<_RangeAlgPolicy>(std::move(__first), std::move(__middle), std::move(__last));
40     return {std::move(__ret.first), std::move(__ret.second)};
41   }
42 
43   template <permutable _Iter, sentinel_for<_Iter> _Sent>
44   _LIBCPP_HIDE_FROM_ABI constexpr subrange<_Iter> operator()(_Iter __first, _Iter __middle, _Sent __last) const {
45     return __rotate_fn_impl(std::move(__first), std::move(__middle), std::move(__last));
46   }
47 
48   template <forward_range _Range>
49     requires permutable<iterator_t<_Range>>
50   _LIBCPP_HIDE_FROM_ABI constexpr borrowed_subrange_t<_Range>
51   operator()(_Range&& __range, iterator_t<_Range> __middle) const {
52     return __rotate_fn_impl(ranges::begin(__range), std::move(__middle), ranges::end(__range));
53   }
54 };
55 
56 inline namespace __cpo {
57 inline constexpr auto rotate = __rotate{};
58 } // namespace __cpo
59 } // namespace ranges
60 
61 _LIBCPP_END_NAMESPACE_STD
62 
63 #endif // _LIBCPP_STD_VER >= 20
64 
65 _LIBCPP_POP_MACROS
66 
67 #endif // _LIBCPP___ALGORITHM_RANGES_ROTATE_H
68